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Capturing Solar Power With Antennae

CmdrTaco posted more than 3 years ago | from the those-bugs-are-gonna-get-headaches dept.

Power 190

necro81 writes "Researchers at the University of Missouri and the Idaho National Laboratory have demonstrated a new method of capturing solar power. Rather than using semiconductors to capture photons of sunlight, they fabricated small coiled antennae (several um square) that resonate with the wave nature of light. The antennae are tuned towards midrange infrared light (5-10 um), which is abundant on our cozy-warm Earth — even at night. They also demonstrated a way to imprint these coils on a substrate, like how CDs or vinyl records are produced, but could be scaled to roll-to-roll mass production. The usual caveat applies: it may be 5-10 years until this could hit the market."

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190 comments

Slow down and THINK before you use these. (0, Offtopic)

Dr.Bob,DC (2076168) | more than 3 years ago | (#36158244)


If these become commercialized it will be a disaster. These micro antennae will effectively absorb midrange IR light and reflect everything else back out as polarized light minus the IR. This is sure to cause skin cancer, retinal damage and other maladies.

Think about it this way: you require an across the board, nutritious meal of food as healthy fuel. Take away the IR light and you're eliminating full spectum light which is essential for health and nervous system maintainence. Make the remaining light polarized and *bam*: a public health disaster in the making. Subluxations Galore.

I was at a seminar in which suntanning booths ("Cancer Coffins") and their effects on spinal nerve health were discussed (hint: don't tan in those things!) The presenter is a well respected chiropractic doctor and researcher in Florida. In fact you can find his his videos on YouTube (look for "Maximized Living") with many thumbs up ratings.

At the break, we were chatting and he said he had seen an increase in the number of serious vertebral subluxations in people who went *TO 3D MOVIES*.

He went on to explain his theory. It seems that the 3D movies these people went to were all the type with strong polarized lighting being projected on the screen. *NONE* of his patients were at the red-blue type of 3D movie. Not one.

So these innocent people go sit in these movie houses as a treat and end up bathing themselves in dangerous polarized lighting. The worst bit is that so many kids movies are 3D now. Young spines and nervouse systems are being destroyed by this nonsense. No wonder we're seeing an increase in the number of parents bringing in their children for chipropractic care.

The public will never hear of this as big media and hollywood will silence critics..

Think about it: after a long movie, doesn't your back feel kind of stiff when you get up? That's caused by micro-subluxations. Moving around breaks those up without any long term damage, but go home and sit on the couch and they grow into full-bore, dangerous, health damaging subluxations. Those are, frankly, worse than cancer.

Think about that before you put up these solar cells.

Take care!
Bob

PS: I can only post once or twice a day (thanks, BP shills) so I may not be able to reply.

Re:Slow down and THINK before you use these. (1)

Anonymous Coward | more than 3 years ago | (#36158314)

You lost me at "chiropractic doctor". No such thing, sorry guy.

Re:Slow down and THINK before you use these. (1, Informative)

Dr.Bob,DC (2076168) | more than 3 years ago | (#36158374)

Doctor of Chiropractic (DC) are indeed doctors.
http://en.wikipedia.org/wiki/Chiropractic_education [wikipedia.org]

Re:Slow down and THINK before you use these. (1)

doti (966971) | more than 3 years ago | (#36158650)

but not a well respected chiropractic doctor

Re:Slow down and THINK before you use these. (1, Informative)

mldi (1598123) | more than 3 years ago | (#36158706)

Doctor of Chiropractic (DC) are indeed doctors. http://en.wikipedia.org/wiki/Chiropractic_education [wikipedia.org]

But not medical doctors. Considering the subject at hand was medical, all reputation is out the window.

Re:Slow down and THINK before you use these. (0)

Anonymous Coward | more than 3 years ago | (#36158814)

Calling yourself doctor does not make you a doctor. Just like dentists. Either do a PhD, or try the 10,000 hours of medical school or 8000 hours of law school if you want to be a real "doctor".

Re:Slow down and THINK before you use these. (1)

Anonymous Coward | more than 3 years ago | (#36159092)

Doctor of Chiropractic (DC) are indeed doctors.

Nope, you're quacks. You're actually more dangerous than most quacks in the placebo business, because some of you quacks break people's necks and spines.

Re:Slow down and THINK before you use these. (1, Informative)

Fjandr (66656) | more than 3 years ago | (#36158708)

Yup, the correct term is "Doctor of Chiropractic," though I'm sure that's not what you actually meant.

No, it's not an MD. The term "doctor" is fairly general, and used in a wide manner to mean people other than those who can prescribe controlled substances or perform surgery.

Re:Slow down and THINK before you use these. (1)

benjfowler (239527) | more than 3 years ago | (#36158438)

You're completely nuts.

subluxations LOL (4, Funny)

fyngyrz (762201) | more than 3 years ago | (#36158466)

Phrenologically speaking, your entire post is really lumpy. From a cooking standpoint, your pot is cracked. And scientifically speaking... well, why bring science into it now?

Re:Slow down and THINK before you use these. (0)

Anonymous Coward | more than 3 years ago | (#36158476)

so polarized light can cause your vertebra to dislocate? how? what happens when I wear my polarized sunglasses? sounds like a quack making money from speaking engagements.

Re:Slow down and THINK before you use these. (0)

Anonymous Coward | more than 3 years ago | (#36158520)

I thought you might be telling a joke with a straight face.
Then I came to the part about the presenter being "a well respected chiropractic doctor" and I knew that was indeed the case. You're funny.

Re:Slow down and THINK before you use these. (1)

Brett Buck (811747) | more than 3 years ago | (#36158522)

. These micro antennae will effectively absorb midrange IR light and reflect everything else back out as polarized light minus the IR. This is sure to cause skin cancer, retinal damage and other maladies.

    You mean that it will spew more UV and other light out than went into it? Making it worse than the same exposure without absorbing the IR?

      Go ask your medical school for your money back, *quick*, because even a doctor should understand the fundamentals of thermodynamics.

Re:Slow down and THINK before you use these. (1)

Anonymous Coward | more than 3 years ago | (#36158642)


Go ask your medical school for your money back, *quick*, because even a doctor should understand the fundamentals of thermodynamics

The vast majority (all?) "Doctors of Chiropractic" have never attended medical school. They go to chiropractic colleges which bestow the academic title of "Doctor" on them. Don't be fooled, they are not medical doctors.

Re:Slow down and THINK before you use these. (1)

Dunbal (464142) | more than 3 years ago | (#36158828)

They are, however, masters at getting the gullible to part with their money.

Re:Slow down and THINK before you use these. (0)

Anonymous Coward | more than 3 years ago | (#36158526)

I don't think you have any Idea what you're talking about.

You seem to be of the opinion that the presence of these antennae are removing the IR from light that doesn't strike them (which is idiotic). You also seem to be poorly isolating variables and correlations with your attribution of a causal relationship between polarized light and "vertebral subluxations". Did you realize that the light from most modern computer monitors and a sigifigant portion of natural light is polarized?

Re:Slow down and THINK before you use these. (1)

Anonymous Coward | more than 3 years ago | (#36158568)

ALL smooth reflective surfaces reflect mostly-polarized light, dipshit. That's why polarizing sunglasses work.

Re:Slow down and THINK before you use these. (1)

Gogogoch (663730) | more than 3 years ago | (#36158616)

hahaha

Re:Slow down and THINK before you use these. (1)

slackzilly (2033012) | more than 3 years ago | (#36158688)

What does micro-subluxations have to do with polarized light?

If you sit in a movie theater seat for two hours without polarized light I am pretty sure you will experience the same effect.

Re:Slow down and THINK before you use these. (1)

retchdog (1319261) | more than 3 years ago | (#36158782)

the "lux" part, i guess. :-/

Re:Slow down and THINK before you use these. (1)

slackzilly (2033012) | more than 3 years ago | (#36159142)

You didn't google the word subluxations did you.

Re:Slow down and THINK before you use these. (2)

GameboyRMH (1153867) | more than 3 years ago | (#36158746)

Parent is successfully trolling the shit out of everyone.

Re:Slow down and THINK before you use these. (1)

NeutronCowboy (896098) | more than 3 years ago | (#36158798)

A classic troll. Well done.

Re:Slow down and THINK before you use these. (0)

Anonymous Coward | more than 3 years ago | (#36158804)

Did you know that those subluxuations you're talking about, the core tenets of chiropractics, are bullshit? You even debate amongst yourself about what the fuck they are.

These vertebral subluxuations, if you chiropractors could agree on what they are, have nothing to do with any illness and treating them does nothing.

Your living in a make-believe castle made out of bullshit. Wake up. Pick a new world view that isn't based on lies.

Re:Slow down and THINK before you use these. (1)

Skidborg (1585365) | more than 3 years ago | (#36159174)

You do realize that he posts almost this exact same post on every few threads merely to generate responses like yours?

As long as its not 7 years away... (0)

RandomChars (1455331) | more than 3 years ago | (#36158264)

Re:As long as its not 7 years away... (1)

uhoreg (583723) | more than 3 years ago | (#36158780)

I think this is a more relevant comic: http://xkcd.com/678/ [xkcd.com]

Re:As long as its not 7 years away... (1)

jemtallon (1125407) | more than 3 years ago | (#36158806)

I concur. Original post is dated 2008... so their prediction is now 7 years away, making it made up

Re:As long as its not 7 years away... (0)

Anonymous Coward | more than 3 years ago | (#36158852)

Ah, but don't forget the researcher translation [xkcd.com]

And 5-10 years from now... (3, Interesting)

elrous0 (869638) | more than 3 years ago | (#36158280)

It will still be 5-10 years away.

Antennas (5, Informative)

LearnToSpell (694184) | more than 3 years ago | (#36158282)

Antennae are for bugs.

Re:Antennas (0)

Anonymous Coward | more than 3 years ago | (#36158482)

Thank you, you saved me the trouble.

Re:Antennas (1)

icebraining (1313345) | more than 3 years ago | (#36159152)

Thank you. They even use Antennas in TFA, so why did the submitter screw up? I know, I must be new here.

Appropriate username, btw.

Most important point not in summary (3, Insightful)

GameboyRMH (1153867) | more than 3 years ago | (#36158310)

The summary fails to mention the most important advancement here: 90%+ efficiency. That's a game-changer for solar power.

Re:Most important point not in summary (5, Insightful)

joe_frisch (1366229) | more than 3 years ago | (#36158370)

What are they using to rectify the signal to convert to DC? The antenna is neat - but not at all surprising, its size should just scale with wavelength. You could make a 125nm long antenna that would resonate with visible light (well withing the resolution of existing lithography). The problem is how to convert the 100THz signal you get to a DC signal. You need a fantastically fast diode.

If they have managed this, that would be an impressive achievement. The fastest diodes I am aware of are around 1THz, but its well outside my field and there might be something faster out there

BTW: the efficiency isn't all the impressive. For single frequency light, conventional solar cells can be quite efficient (~80%???), but they don't do will with broad thermal light (like sunlight). The photons that are less than a band-gap don't do anything, and the ones above a bandgap waste any excess energy.

Re:Most important point not in summary (4, Informative)

Brett Buck (811747) | more than 3 years ago | (#36158486)

I think you see the problem - I *am* in a related field and I certainly don't know of any practical or efficient way to rectify it. I can think of absurdly inefficient ways, but we already have a bunch of those.

Re:Most important point not in summary (1)

Anonymous Coward | more than 3 years ago | (#36158714)

How about.. have two slightly different antenna sizes on the substrate. Mix the super high frequency stuff together to get a beat frequency you can rectify with cheap and cheerful silicon diodes.

Probably a million reasons why it won't work, but I may as well throw it out there...

( If it does trigger the solar revolution and somebody gets very rich, don't forget to send some my way ;-) )

Re:Most important point not in summary (1)

Anonymous Coward | more than 3 years ago | (#36159256)

But then you'd need a super-high-frequency mixer...

Re:Most important point not in summary (1)

mldi (1598123) | more than 3 years ago | (#36158802)

I would imagine this is why we aren't powering space stations on the dark side of earth with giant laser beams? Because that idea tickles me.

Re:Most important point not in summary (2)

pz (113803) | more than 3 years ago | (#36158898)

Might there be an efficient way to frequency scale the signal and bring it down to usable levels? Or does the fact that we're talking about light-scale dimensions mean most of what we think about in terms of EE is not applicable?

Re:Most important point not in summary (1)

Nethemas the Great (909900) | more than 3 years ago | (#36159312)

I'm totally out of my depth on this (so please forgive my ignorance...) but perhaps if I'm understanding properly we've already got a start [manchester.ac.uk] on rectifying THz radiation [library.ethz.ch] .

Re:Most important point not in summary (1)

dbc (135354) | more than 3 years ago | (#36158594)

Yes, antennas tend to be very narrow band. Rectification is the key here... I remember hearing about somebody using nano-antennas to capture solar energy in the early 80's... back then, though, they figured they were 5-10 years away from having something ready for the market.

Re:Most important point not in summary (1)

chemicaldave (1776600) | more than 3 years ago | (#36158644)

Alas, the authors mention this indirectly. Emphasis mine:

More extensive research needs to be performed on energy conversion methods to derive overall system electricity generation efficiency. ... This research is at an intermediate stage and may take years to bring to fruition and into the market. The advances made by our research team have shown that some of the early barriers of this alternative PV concept have been crossed and this concept has the potential to be a disruptive and enabling technology.

At least they made actual progress in this paper with real models. That's more than can be said for the hundreds of theoretical models.

Unobtainum diodes (4, Informative)

Animats (122034) | more than 3 years ago | (#36158830)

What are they using to rectify the signal to convert to DC?

Unobtainum diodes. They don't actually know how to do that.

Terahertz diodes do exist [vadiodes.com] . Low-cost, high-efficiency, integrated terahertz diodes, no. But as work proceeds on terahertz electronics, someone may solve that problem. Each nanoantenna needs its own nanodiode, so the diodes have to be fabricated on the substrate with the antenna, which complicates the fab problem. The enthusiasm about roll-to-roll low cost fabrication in the article is premature. We'll probably see this working first on a wafer, and it may not be cheap.

Even if it's expensive, there's an initial market for satellite power panels. The performance improvement would be worth it.

Re:Unobtainum diodes (5, Informative)

joe_frisch (1366229) | more than 3 years ago | (#36158908)

I've bought some 300Ghz diodes from Virginia Diodes. Worked great, but $7K each as I remember......

Here they need more like 100 THz. Might be possible with some sort of nonlinear optical material, but the fields are probably much too low.

Even if this whole scheme does work, its not clear it is any better than a conventional solar cell - they are quite efficient for narrow-band radiation right above their bandgap. You can stack different band-gap solar cells to get a quite efficient stack, but it doesn't make economic sense - sunlight is free, its the solar cells that cost money......

Re:Unobtainum diodes (2)

Intrepid imaginaut (1970940) | more than 3 years ago | (#36159250)

its not clear it is any better than a conventional solar cell

Working at night is a decent beneift.

Re:Most important point not in summary (1)

Em Adespoton (792954) | more than 3 years ago | (#36158992)

Seems to me that once they get a decent diode, these could be used as air cooling systems, with generated power as a positive side effect.

Re:Most important point not in summary (1)

LWATCDR (28044) | more than 3 years ago | (#36159154)

What about doing the reverse? Use this to produce light? Maybe for a monitor or screen. Yes no the problem is to make a lot of really cheap transmitters. Maybe really tiny magnetrons?

Re:Most important point not in summary (2)

i_b_don (1049110) | more than 3 years ago | (#36159266)

What? Best in class photovoltaic solar cells, in university settings under optimal conditions are around 43%-44%. That's the top efficiency of some very complex structures that are not mass producible using a light source that's 80x normal. 80% is unheard of. In fact, as I was thought in school 15 years ago, the theoretical maximum efficiency of the transistor solar cell method is 50%, thus the reason that 43% is considered really damn good. 80% is god-like.

d

Re:Most important point not in summary (1)

drerwk (695572) | more than 3 years ago | (#36158402)

The P fails to notice that they are not yet able to rectify the current, and hence can not yet get power out, and so the 90% number is only for antenna coupling, not conversion to DC current.

More extensive research needs to be performed on energy conversion methods to derive overall system electricity generation efficiency.

It is like saying current solar cells are 90% efficient because 90% of photons are absorbed; it says nothing about the quantum efficiency of conversion. I am willing to bet that the QM Efficiency of the necessary rectifier will be the big loss; though it may only be 50%.

Re:Most important point not in summary (0)

Anonymous Coward | more than 3 years ago | (#36158410)

Unfortunately that's not across the solar spectrum but in a small band in mid-IR that is very low in actual power from the sun. I saw the 90% quoted on another site erroneously.

Re:Most important point not in summary (0)

Anonymous Coward | more than 3 years ago | (#36158478)

90% for that range of frequency which i bet is quite small in comparison to regular solar power. This definitely sounds like a good possibility but the total energy they can get is from a smaller pool though this may not matter due to higher efficiency but most importantly, cheapness.

Re:Most important point not in summary (1)

CCarrot (1562079) | more than 3 years ago | (#36158744)

90% for that range of frequency which i bet is quite small in comparison to regular solar power. This definitely sounds like a good possibility but the total energy they can get is from a smaller pool though this may not matter due to higher efficiency but most importantly, cheapness.

Actually, it sounds like by varying the size and materials of the antennas on a panel, they can capture a much broader spectrum of light than 'conventional' panels, including extending into the infrared.
https://inlportal.inl.gov/portal/server.pt?open=514&objID=1269&mode=2&featurestory=DA_101047 [inl.gov]

There are definite and novel uses for this, if they could figure out how to actually rectify the electricity generated. Industry, for example, spends big dollars trying to shed waste heat from piping and equipment...how about wrapping it in one of these and let the generated electricity run your cooling system for you? Talk about direct waste heat recovery systems...I picture a solar farm with their 'panels' gently flapping in the breeze, not caring about incident light direction, so long as they're in the sunlight...and still keeping the lights on for some time after the sun goes down...

good times.

Re:Most important point not in summary (1)

Rei (128717) | more than 3 years ago | (#36159466)

I can't help but wonder about the entropy aspect. I mean, you're taking away blackbody radiation and turning it into power at extreme efficiency so that you can get work done all over again. Doesn't that strike anyone else as odd? I mean, let's say that you've got an engine near the Carnot limit and you wrapped it in these IR solar cells, which take 90% of the radiated waste heat and turn it into electricity, when you then use to power an electric motor to boost your engine's output. Would you not have just surpassed the Carnot limit?

Re:Most important point not in summary (3, Insightful)

lupine (100665) | more than 3 years ago | (#36158510)

From TFA:
The individual nantennas can absorb close to 90 percent of the available in-band energy.

So the total system efficiency depends on how wide that band is in relation to total solar energy available and whether nantennas can be stacked and designed to capture energy over a range of bands.

Re:Most important point not in summary (3, Interesting)

skids (119237) | more than 3 years ago | (#36158816)

Such a system would be yet another layer in the panel to deal with a specific frequency range. Perhaps several layers with different wavelengths in each. It's journalists that make the mistake of promoting this as a whole solar panel.

That said, the rectification issue is a deal killer. Not only are we talking THz, but IIRC from the last media go-round with this technology, voltages way below practical diode thresholds.

Ressonance good for communication not power (2)

erice (13380) | more than 3 years ago | (#36158912)

The individual nantennas can absorb close to 90 percent of the available in-band energy.

Which is good for communications, where you want to exclude all but the target band. It could even work for power, providing the light source is a laser. But resonance methods aren't very good for capturing energy from broad spectrum sources like the sun.

I predict that this technique will never gain traction for solar energy. However, it might replace photodiodes for fiber optic communications.

Re:Ressonance good for communication not power (1)

wagnerrp (1305589) | more than 3 years ago | (#36159282)

MASERs and rectenna already operate using this same principle, and similarly operate at 85% or better efficiency. Since they operate in the tens of GHz range, there are readily available electronics available to handle them.

Re:Ressonance good for communication not power (3, Funny)

demonbug (309515) | more than 3 years ago | (#36159448)

MASERs and rectenna already operate using this same principle, and similarly operate at 85% or better efficiency. Since they operate in the tens of GHz range, there are readily available electronics available to handle them.

Cartman had one of those, right?

Re:Most important point not in summary (2)

blair1q (305137) | more than 3 years ago | (#36158620)

Solar efficiency is measured as usable power output vs. total incident power across the full incident spectrum.

This thing's efficiency is measured as usable power output vs. power across the very small bandwidth it detects. Which is to say, its solar efficiency is probably in the micro-percents.

Re:Most important point not in summary (1)

nanohurtzGT (1114555) | more than 3 years ago | (#36158796)

Nothing new, this was developed years ago, and took the approach of microvibrators. If only this were a resource based economy. This would hit the market tomorrow... * tosses the idea with the rest of the pile including the flying car, and the transatlantic super train *

Re:Most important point not in summary (0)

Anonymous Coward | more than 3 years ago | (#36159016)

But that's not overall efficiency, mind you. 90% of the energy in the band that resonates with the antenna is collected. Then electrons still have to go through a rectifier. All in all, efficiency should be better than actual photo-voltaic cells, but not that much better.

Re:Most important point not in summary (1)

wagnerrp (1305589) | more than 3 years ago | (#36159298)

This is nothing more than a rectenna, scaled down to operate at optical wavelengths. Rectenna in the microwave band already operate with 85-90% usable generated electricity. The problem is that while we have electronics fast enough to rectify a microwave signal in the tens of GHz, we have nothing that even comes close to rectifying an optical signal in the hundreds of THz.

Re:Most important point not in summary (1)

jcr (53032) | more than 3 years ago | (#36159098)

Isn't that only for the particular band it's tuned to absorb?

-jcr

Re:Most important point not in summary (1)

whiteboy86 (1930018) | more than 3 years ago | (#36159164)

Not 90% efficiency over whole light energy spectrum, but in a certain frequency band the antenna is tunned to, that means 90% efficiency in a narrow band of light energy.

The biggest technical problem with the substrate (1)

Anonymous Coward | more than 3 years ago | (#36158334)

Currently, they can only make these these things work with a flying car as the substrate.

Rectification is the hard part (1)

Anonymous Coward | more than 3 years ago | (#36158338)

Rectifier? Just sayin'. Can't run your stuff off of THz electricity.

Re:Rectification is the hard part (1)

Son of Byrne (1458629) | more than 3 years ago | (#36158748)

Can't run your stuff off of THz electricity.

Why not?

I know I sound like a dolt, but maybe that's the game changing question?

Anyone have any thoughts on why we can't "run our stuff off of THz electricity?"

Re:Rectification is the hard part (0)

Anonymous Coward | more than 3 years ago | (#36158866)

Inductance and parasitic capacitance.

Your THz electric signal is going to go everywhere except down the wire.

Re:Rectification is the hard part (1)

vlm (69642) | more than 3 years ago | (#36158920)

Inductance and parasitic capacitance.

Your THz electric signal is going to go everywhere except down the wire.

The other problem is there really is nothing useful to do with THz AC.

You can't really do anything "useful" with 60 Hz AC without rectifying it, or doing some AC motor stuff. I think it would take a rather large number of "poles" to make a three phase motor run off THz AC, and as you note, the inductance makes it unbuildable, so we won't be doing either the electric or the electronic thing.. leaving us with not much. Resistive heating?

Re:Rectification is the hard part (2, Insightful)

Anonymous Coward | more than 3 years ago | (#36158886)

The simple answer is that electronics aren't instant. Every single wire and component in any device you can build actually acts like a resistor, capacitor, and inductor. The combination of these effects means that when you, say, apply a voltage to a wire, it takes some tiny amount of time to "charge up". Even with the gigahertz frequencies used in processors, things have to be specifically built (and be tiny) to work with these charge times. If you try and do anything with *terahertz* frequencies? Even a micrometer of wire won't be "charged' before the wave goes negative, at which point it discharges... and you wind up with an average of zero volts.

TL;DR: Until we have wire made out of superconductor, frequencies that high simply can't be transfered through circuits.

Re:Rectification is the hard part (0)

Anonymous Coward | more than 3 years ago | (#36158788)

OK, sincere and possibly stupid question here; can't you run a pure resistance load of THz electricity?

If so, you could maybe use this for solar thermal rather than photoelectric (!) - wire a bunch of these up to a resistance coil and drive a heat engine (steam turbine) off of that...

Re:Rectification is the hard part (1)

Maddog Batty (112434) | more than 3 years ago | (#36159106)

At the moment, the energy absorbed by the antenna isn't going anywhere as nobody has invented a suitable diode. It therefore will just end up as heat anyway.
This isn't actually gaining you anything as a black sheet of paper will do this job equally as well.

New use for ancient pattern? (0)

Anonymous Coward | more than 3 years ago | (#36158356)

Greeks were way ahead of this with their "key pattern" motif. Who knew it would be useful in ways other than decorative when made microscopic and etched on a semiconductor substrate?

body heat = infrared (1)

dgatwood (11270) | more than 3 years ago | (#36158362)

Anybody else read this and immediately think that it might potentially solve the problem of biologically powering medical implants that was mentioned in a story on Slashdot about a week ago?

Re:body heat = infrared (0)

Anonymous Coward | more than 3 years ago | (#36158662)

Nope just you so you better patent the idea!

Re:body heat = infrared (1)

dgatwood (11270) | more than 3 years ago | (#36158946)

By describing the invention here, at least it should count as publication of prior art in the field, should anyone else attempt to patent it in the future.

Beware (1, Informative)

bananaquackmoo (1204116) | more than 3 years ago | (#36158376)

Beware the PDF link

Re:Beware (1)

icebraining (1313345) | more than 3 years ago | (#36159202)

I just use this [arpitnext.com] to open them in Google Docs Viewer by default; it's all HTML to me.

How hard can it be ... (1)

Skapare (16644) | more than 3 years ago | (#36158392)

... to etch an antenna at the wavelength of 0.000001 meter? Well, OK, it's not trivial. But we do have things like lasers that can etch chemicals at that size and smaller. Then we need a way to transfer that etch to conductive metal, add rectification to make it usable and collectible, and have our own little power sources. A flat panel might do if the current level doesn't burn up the collection tap point.

Re:How hard can it be ... (1)

CCarrot (1562079) | more than 3 years ago | (#36158604)

... to etch an antenna at the wavelength of 0.000001 meter? Well, OK, it's not trivial. But we do have things like lasers that can etch chemicals at that size and smaller. Then we need a way to transfer that etch to conductive metal, add rectification to make it usable and collectible, and have our own little power sources. A flat panel might do if the current level doesn't burn up the collection tap point.

They can 'print' them.
https://inlportal.inl.gov/portal/server.pt?open=514&objID=1269&mode=2&featurestory=DA_101047 [inl.gov]

This seems a bit well-aged for 'breaking' news, unless they've found some way to rectify the high frequency power...then it would be newsworthy indeed! I'll have to RTFA...

Re:How hard can it be ... (3, Informative)

chemicaldave (1776600) | more than 3 years ago | (#36158786)

The newsworthiness is that instead of only 250 million nantennas on one small square like in that INL page, these guys replicated a design onto an "8 inch round silicon wafer" with 10 billion antenna elements. And they did it with high detail and little loss between the "master print" and the copy.

Re:How hard can it be ... (1)

CCarrot (1562079) | more than 3 years ago | (#36159176)

Wow, that is quite impressive! I missed that in my skimming, thanks.

Too bad we still can't do anything with all those antennas unless we can rectify the output...it seems like saying "look at how densely we can pack data into these drive platters!" before anybody has invented the read-write head. But it is good to know they're still trying to develop this idea.

huh wha? (1)

sgt scrub (869860) | more than 3 years ago | (#36158432)

so, does this mean they are making vibrators? i thought vibrators used electricity.

2008? (0)

Anonymous Coward | more than 3 years ago | (#36158470)

Did anyone else notice this paper was written in 2008? That means we are only 2-7 years away! I'll be powering my home with antennas that cover my roof in 2 short years!

If this is such big news, why did it take 3 years to make it to /.?

Nothing new (2)

Maximum Prophet (716608) | more than 3 years ago | (#36158504)

Don Lancaster described this process years ago. The trick is the tiny diode at the bottom of the antenna to turn the AC into DC. It has to handle 400 - 800 THz. Plausible, but difficult. 5-10 years really means they have no idea when they'd be able to produce this in industrial quantities.

Is this a very old idea (1)

Anonymous Coward | more than 3 years ago | (#36158518)

When Tesla was determining the resonant frequencies of the earth to potentially transmit unlimited electric power, he also recognized frequencies that acted as a damping field to nullify electric power. With the advent of the wireless and Tesla's unique investigations into broadcasting electricity, a dozen or more inventors thereafter announced their own means for transmitting electrical energy without wires. One British inventor, H. Grindell-Matthews, actually demonstrated his "mystery ray" apparatus in 1924 to a Popular Science Monthly writer in London (See: Pop. Sci. Monthly, Aug. 1924, P. 33). When his beam was directed toward the magneto system of a gasoline engine, it stopped the system. Afterwards, it ignited gun powder, lit an electric lamp bulb from a distance and killed a mouse in seconds! Grindell-Matthews said the secret was involved with the "carrier beam" he used to conduct a high-voltage, low-frequency electrical current. During 1936, Guglielmo Marconi experimented with extremely low frequency (ELF) waves and displayed their exceptional ability to penetrate metallic shielding. These waves could affect electrical devices, overload circuits and cause machines like generators, electric motors and automobiles to stall. Diesel engines, which do not rely on electrical ignition, were not affected. Mysteriously, Marconi's research on the subject was never found after the war.

Re:Is this a very old idea (2)

bmo (77928) | more than 3 years ago | (#36158570)

Amiga fanboys come in second only to Tesla fanboys.

It's 2011.

Tesla's dead.

--
BMO

# of comments gone on front page (1)

fregare (923563) | more than 3 years ago | (#36158556)

Slashes Dot is turning to Shit.t.

Patent the Inevntion! (0)

Anonymous Coward | more than 3 years ago | (#36158624)

Someone made a new break thru invention and they should quickly patent it!
Never mind, patents are useless because no one invents anything by themselves any more.

Thermodynamics is a bitch. (2, Insightful)

Anonymous Coward | more than 3 years ago | (#36158730)

This is, of course, utterly useless for harvesting power from ambient thermal radiation. Even if you can make a diode that's remotely capable of rectifying current at high enough frequencies, the diode has to be kept colder than the source of the radiation. It's the electrical analog of a Brownian ratchet.

Picking up a bit of the IR tail that conventional photovoltaics don't catch? Maybe, but there isn't very much power down there even if you got the efficiency usefully high. Turning ambient heat into usable energy? Sorry, no.

nano devices for rectification (1)

si3n4 (540106) | more than 3 years ago | (#36158754)

http://personalpages.manchester.ac.uk/staff/A.Song/research/BallisticRectifier.htm [manchester.ac.uk] this is the only link I could find , I saw this topic some time ago - the ability to build nano structures may solve the rectification - I am sure there was another paper with a different device configuration but I'll never find the thread now - doesn't make this tomorrow but it means a lead on both ends

Caveats (0)

killmenow (184444) | more than 3 years ago | (#36158810)

The usual caveat applies: it may be 5-10 years until this could hit the market.

The solar constant caveat applies: it will always be 5-10 years until this could hit the market.

ALWAYS.

The problem with solar power (1)

gilesjuk (604902) | more than 3 years ago | (#36158824)

This is the problem with solar power, it's mostly home owners who are buying them and the systems cost so much it takes decades to break even (if purely doing it for cost reasons, not CO2).

So once a better technology comes along you have to junk the old tech and you may never break even.

Re:The problem with solar power (2)

Em Adespoton (792954) | more than 3 years ago | (#36159010)

This is the problem with solar power, it's mostly home owners who are buying them and the systems cost so much it takes decades to break even (if purely doing it for cost reasons, not CO2).

So once a better technology comes along you have to junk the old tech and you may never break even.

Hello 1978, welcome to 2011 where panels pay for themselves within 4 years, have a lifespan of 20+ years, and are significantly cheaper to produce and use less-rare components.

Re:The problem with solar power (0)

Anonymous Coward | more than 3 years ago | (#36159030)

As a former horse and buggy owner and current owner of an android phone, I agree with your sentiments.

Yawn (1)

wcrowe (94389) | more than 3 years ago | (#36158966)

Yeah, I'm still waiting on the amazing solar innovations that were breathlessly announced five years ago to hit the market.

like dog years, but rather... (1)

arikol (728226) | more than 3 years ago | (#36159032)

Is this 5-10 flying car years? Similar to dog years but in the other direction. 1 flying car year equals 1 normal human lifespan, apparently...

Anti-global warming? (1)

hansraj (458504) | more than 3 years ago | (#36159212)

Is it possible that a widespread use of such antennas will lower the average temperature since it is tuned to mid range infra-red? They can sell it being super eco friendly :-)

Re:Anti-global warming? (1)

hansraj (458504) | more than 3 years ago | (#36159230)

'sell it (to target audience) as being.."

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